How much do you know about the simplest golden common sense? Introduction to the Origin of Gold Gold is one of the earliest metals discovered and used. As early as the Neolithic Age (about 65,438+0,000 to 4,000 years ago), human beings had known about gold. At the latest in the middle of Shang dynasty (BC14 ~13rd century), China mastered the technology of making gold wares, and there was gold foil among the cultural relics of Yin Shang unearthed in Anyang, Henan. "Li Zhou Di Guan" said: Iraq (Music Mine) holds a land of gold and jade in its hands. This is the earliest record of mining and metallurgy in ancient literature. It is said that during the Warring States period, with the development of commerce, gold became the common currency, and the feudal ruling class's demand for luxury life decoration increased. Guan Di Zi Shu, written by Guan Zhong, a famous Qi Xianggong in the Spring and Autumn Period, said: "There is cinnabar on the top and gold on the bottom; There are magnets above and copper below. " Load.

Gold, also known as gold, English gold, chemical symbol Au, atomic number 79, is an orange-yellow metallic substance. In nature, gold exists in the form of simple materials.

I. Characteristics

The density is very high. At normal temperature and pressure, the density of gold is 19.32g/cm3, which is nearly 20 times that of water and more than 3 times that of iron.

Both melting point and boiling point are very high, melting point 1064.43℃ and boiling point 2808℃. As the saying goes, "real gold is not afraid of fire."

Mohs hardness is 2.5, which is equivalent to human nails.

Good toughness and ductility. One gram of pure gold can be drawn into a filament of more than 3000 meters, or forged into a gold foil of 9 square meters.

High stability, strong corrosion resistance, insoluble in other acid and alkali solutions except aqua regia. The gold funerary objects unearthed in the ancient tomb are as bright as new despite thousands of years of wind and rain.

Second, the expression of gold fineness

The fineness of gold is also the purity of gold, which refers to the content of gold in gold products. There are two popular ways to express the purity of gold:

K-gold method:

That is to say, gold with a gold content of 100% is called 24K gold (lK=4. 1666%). Similarly, the gold content of 18K gold is 75%, that of 14K gold is 50% and that of 9K gold is 37.5%.

Proportional method:

It is expressed in percentages and thousandths. For example, Au99.95 is 99.95% gold and Au999.5 is 999.5‰ gold.

Third, the unit of gold.

1, European and American troy ounce system.

1 troy horn = 3 1. 103495g

2. Hongkong, Japan and China balanced the two systems in ancient times.

1 Sima Liang = 37.3438+0 g.

1 yen = 3.75g

1 kg = 1 6 = 500g,1two = 31.25g.

3. Municipal units of measurement. Now Shanghai gold is in grams.

1 kg = 10 two = 500g.

4, South Asia, New Delhi, Karachi, Mumbai and other Torah scales.

1 tora =11.6638g.

Fourth, the world's major gold markets.

1, London gold market, established in 19 19, is the largest spot trading center in the world. There is no fixed exchange in the London gold market, and its transactions are mainly completed through the invisible hand segment-the sales contact network of major gold merchants. The trading members are composed of five authoritative gold merchants and some companies or firms that are recognized as qualified to buy gold from the five gold merchants. At the time of trading, gold merchants quote their buying and selling prices according to their respective buying and selling prices. The top five gold merchants in London gold market are:

1) Luo

2) Jin Baoli

3) Wanda Ji

4) Vangada

5) Meisi Pacific

The London Gold Market offers two fixed prices every morning (7: 30) and afternoon (3: 00 sharp). These two fixed prices are important reference prices in the global gold market.

2. American gold market

The New York Mercantile Exchange (hereinafter referred to as COMEX) and Chicago Mercantile Exchange (hereinafter referred to as IMM) are the largest gold futures trading centers in the world, as well as the most active and traded markets in the world. Take COMEX as an example, the daily turnover of gold futures reached 30,000 lots. COMEX's gold price is an important reference for global spot gold prices.

3. The Shanghai Gold Exchange, established on October 30th, 2002, is an important symbol of the reform of gold management system in China, the marketization of gold and the end of the national unified purchase and distribution system.

The first members of Shanghai Gold Exchange are 108, which are scattered in 26 provinces, municipalities and autonomous regions. Among them, there are 0/3 commercial banks, 3 gold production and smelting units, 6 gold consumption units and 3 coin-making units. The trading hours are from Monday to Friday (except legal holidays) from 10: 00 am to1:30 pm to 13: 30 pm. The trading method is membership, and the minimum trading volume is 1 kg, and the trading volume must be an integer multiple of 1 kg.

Due to the trading rules of Shanghai Gold Exchange, ordinary natural person investment consumers cannot directly participate in the gold trading of Shanghai Gold Exchange. There must be an intermediary service provider (gold merchant) to provide small-amount (above 10g) gold investment and consumption varieties for natural persons to invest in consumers, so as to build a bridge for natural persons to participate in gold trading. That's all I know. I hope I can help you do your own research.